Molecular xenomonitoring and host identification of Leishmania sand fly vectors in a Mediterranean periurban wildlife park

The epidemiological cycle of zoonotic phlebotomine‐borne Leishmania infantum is a complex system in which domestic animals and wildlife interact and participate in its maintenance and transmission. In this study, we combined entomological surveillance, xenomonitoring of L. infantum and identification of host feeding sources of engorged females to investigate the potential contribution of a periurban wildlife park to leishmaniosis in neighbouring residential areas. Overall, 7,309 sand flies were collected in 111 trap‐days during the summers of 2016–2018 in an endemic area in south‐east Spain. Five different sand fly species were captured, with Phlebotomus perniciosus, the main L. infantum vector in this region, representing the most common species. Sand fly distribution was spatially heterogeneous in terms of species, sexes and female physiological stage (unfed, gravid and engorged females) and related to host distribution and management, and environmental features. None of the 602 sand flies analysed for L. infantum infection by kinetoplast real‐time PCR were positive. We used molecular tools to identify the vertebrate hosts of sand flies and identified 17 host species, mainly mammals. Human DNA was not identified in engorged sand flies. This study provides evidence that wildlife parks in south‐east Spain are ideal grounds for sand fly vectors but do not necessarily increase L. infantum infection risk to humans and dogs living in surrounding residential areas. This is probably because vectors feed mostly on non‐L. infantum competent hosts and this should be investigated for a better understanding of the contribution of wildlife parks to the local epidemiology of L. infantum.     

Impact of single-room contact precautions on hospital-acquisition and transmission of multidrug-resistant Escherichia coli: a prospective multicentre cohort study in haematological and oncological wards

ObjectivesColonization and infection with third-generation cephalosporin-resistant Escherichia coli (3GCR-EC) are frequent in haematological and oncological patients. In this high-risk setting, German guidelines recommend single-room contact precautions (SCP) for patients with 3GCR-EC that are non-susceptible to fluoroquinolones (F3GCR-EC). However, this recommendation is controversial, as evidence is limited.MethodsWe performed a prospective, multicentre cohort study at four haematology and oncology departments assessing the impact of SCP on hospital-acquired colonization or bloodstream infection (BSI) with F3GCR-EC. Two sites performed SCP for F3GCR-EC patients including single rooms, gloves and gowns (SCP sites), and two did not (NCP sites). Active screening for 3GCR-EC was performed and isolates were characterized with molecular typing methods including whole genome sequencing and core genome multiple locus sequence typing to assess patient-to-patient transmission. Potential confounders were assessed by competing-risk regression analysis.ResultsWithin 12 months, 1386 patients at NCP sites and 1582 patients at SCP sites were included. Hospital-acquisition of F3GCR-EC was observed in 22/1386 (1.59%) and 16/1582 (1.01%) patients, respectively (p 0.191). There were 3/1386 (0.22%) patients with BSI caused by F3GCR-EC at NCP sites and 4/1582 (0.25%) at SCP sites (p 1.000). Patient-to-patient transmission occurred in three cases at NCP and SCP sites each (p 1.000). The number of patients needed to screen in order to prevent one patient-to-patient transmission of F3GCR-EC was determined to be 3729.ConclusionsUse of SCP had no significant impact on hospital-acquisition or patient-to-patient transmission of F3GCR-EC in this high-risk setting.     

Early prenatal vitamin D concentrations and social-emotional development in infants

Background: Many pregnant women in the United States have suboptimal vitamin D, but the impact on infant development is unclear. Moreover, no pregnancy-specific vitamin D recommendations have been widely accepted.

Aims: Given the ubiquitous expression of vitamin D receptors in the brain, we investigated the association between early prenatal plasma 25-hydroxyvitamin D (25(OH)D) concentrations and children’s social and emotional development in the Newborn Epigenetic Study, a prospective study of pregnancies from 2009 to 2011 in Durham, North Carolina.

Methods: We measured 25(OH)D concentrations in first or second trimester plasma samples and categorized 25(OH)D concentrations into quartiles. Covariates were derived from maternal questionnaires. Mothers completed the Infant Toddler Social-Emotional Development Assessment when children were 12–24 months of age. We used multivariable linear regression to evaluate associations between 25(OH)D and specific behavior scores, adjusted for season of blood draw, maternal age, education, parity, smoking, marital status, prepregnancy BMI, and infant gender. We investigated effect-measure modification by race/ethnicity.

Results: Of the 218 mother–infant pairs with complete data, Black mothers had much lower 25(OH)D concentrations as compared to White and Hispanic mothers. After adjustment, lower prenatal 25(OH)D was associated with slightly higher (less favorable) Internalizing scores among White children, but lower (more favorable) Internalizing scores among Black and Hispanic children. Lower prenatal 25(OH)D also appears to be associated with higher (less favorable) dysregulation scores, though only among White and Hispanic children.

Conclusions: Though imprecise, preliminary results warrant further investigation regarding a role for prenatal vitamin D on children’s early social and emotional development.